Quick Links

How would you like to share?

A report in the current issue of the Archives of Neurology suggests yet again that cholesterol has some link with Alzheimer's disease. Kristine Yaffe and colleagues at the University of California, San Francisco, and elsewhere, found evidence that LDL cholesterol (the "bad" kind), as well as total cholesterol, was associated with worse cognitive scores and a greater likelihood of cognitive impairment in a study of 1,037 postmenopausal women. Conversely, among women who reported using cholesterol-lowering drugs called statins during the final month of the four-year study, there was a trend in the data toward better results on the cognitive tests. This difference appeared to be independent of total cholesterol level. The study's data are difficult to interpret, however, because the women received no cognitive tests at baseline.—Hakon Heimer

Comments

Comments on this content

Jick et al., 2000; Wolozin et al., 2000). On the other hand, the literature linking cholesterol and cognitive decline is less clear, because some studies have suggested that ApoE4, rather than cholesterol, is more strongly associated with cognitive decline (Jarvik et al., 1995). The current study supports a relationship between cholesterol and cognitive decline, but does not dissect out the respective roles of ApoE4 and cholesterol. Further studies will be needed to clarify this issue.

The exact mechanism is unclear. Cholesterol level clearly modulates Aβ production, but it is unclear whether peripheral cholesterol and statins that have poor CNS penetration can actually lower Aβ in the brain at normal therapeutic doses of statins (Fassbender et al., 2001; Refolo et al., 2001; Simons et al., 1998; Wolozin, 2001). In addition, it is important to note that other cholesterol-related compounds, such as cholesterol esters, also modulate Aβ production (see ARF news item). Peripheral cholesterol or statins could also impact on apoE in the CNS, and on endothelial health (see ApoE chat transcript). Hence, multiple mechanisms could account for the putative protective effect of statins. What does appear to be increasingly clear, though, is that a protective effect does exist and is therefore worth investigating.